1. Field of the Invention
The present invention relates generally to methods for manufacturing skis for use upon snowmobiles and like vehicles that operate upon snow, and more specifically it relates to a method of manufacturing a ski for creating a preload force upon a front portion of a ski in combination with a resilient preload member.
2. Description of the Prior Art
Skis for snowmobiles and like vehicles have been in use for years. A snowmobile or like vehicle typically is comprised of a frame, a track within the rear portion of the vehicle, and a pair of skis controllably attached to a steering structure of the vehicle. Skis are utilized for supporting and steering the vehicle during operation upon snow and other surfaces.
Skis for snowmobiles and like vehicles are typically constructed of either metal, or a combination of metal and plastic. Regardless of the material utilized, conventional skis for snowmobiles and like vehicles are manufactured utilizing the same process as shown in FIGS. 1 and 2 of the drawings. More particularly, the ski is molded with the desired curvature within the front portion of the ski and a loop member is attached to the tip of the front portion and the ski without stressing the front portion of the ski (i.e. the front portion is in a relatively relaxed state). FIGS. 1 and 2 also illustrate the usage of a rigid metal saddle removably attached to an upper surface of the ski body for securing to the snowmobile.
Regarding metal only skis, each ski is formed into an elongate rigid structure having a relatively straight rear to middle portion with a front portion containing a desired curvature utilizing conventional metal working procedures without stress existing within the front portion. A stiff loop member, usually constructed of an elongate metal rod structure, is attached to the front end of the ski and to the middle portion of the ski. The loop member is typically welded to the front end of the ski and to the middle portion of the ski. The loop member is designed for preventing the pointed front end from injuring a third-party, for grasping when attempting to move the snowmobile, and for increasing the overall strength of the front portion when encountering obstacles during forward movement of the vehicle.
More recently, skis for snowmobiles and like vehicles have been constructed of a combination metal and resilient plastic, such as ultra high molecular weight (UHMW) polyethylene, which allows for increased flexibility of the ski when encountering obstacles. The main body of the ski is comprised of a plastic material typically manufactured utilizing injection molding or blow molding wherein the rear portion to middle portion is molded relatively straight with the front portion molded to possess the desired curvature without stress existing within the front portion. A rigid metal saddle is attached to the middle portion of the plastic ski for allowing attachment of the ski to the front suspension of the snowmobile. A loop member, typically constructed of plastic, is attached to the front end of the ski and then to the middle portion of the ski with no stress contained within the front portion thereof. As with loop members utilized with metal skis, the loop member is designed for preventing the front end of the ski from injuring a third-party, for grasping when attempting to move the snowmobile, and for increasing the overall strength of the front portion when encountering obstacles during forward movement of the vehicle.
One of the main problems with conventional ski manufacturing processes, for either metal or metal-plastic skis, is that they mold the front portion of the ski into the desired curvature and then secure a loop member between the middle of the ski to the front end of the ski in order to keep the front end of the ski from bending rearwardly when engaging obstacles. A further problem with conventional ski manufacturing processes is that they cause the front portion of the ski to be less flexible because of the loop member attempts to keep the front end of the ski in the current position. A further problem with conventional ski manufacturing processes is that the combination of the loop member and the static curved portion creates a rigid structure that is unable to significantly flex when encountering an obstacle. Another problem with conventional ski manufacturing processes is that the rigid front portion of the ski attempts to “pivot” about the connection point of the loop member in the middle portion of the ski since the front portion is unable to significantly flex when encountering an obstacle.
While conventional ski manufacturing processes may be suitable for the particular purpose to which they address, they are not as suitable for creating a preload force upon a front portion of a ski utilizing a resilient preload member thereby enhancing the overall performance of the ski. Conventional ski manufacturing processes create a semi-rigid structure within the front portion of the ski thereby reducing their ability to properly flex when encountering obstacles.
In these respects, the method of manufacturing a ski according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of creating a preload force upon a front portion of a ski in combination with a resilient preload member.